Nowadays, the integration of different function circuit modules into the same semiconductor chip is gradually adopted in the manufacture of an integrated circuit. As known, these function circuit modules have respective operating voltage ranges. It is a challenge of integrating so many function circuit modules with different operating voltage ranges into the same semiconductor chip. In views of the device configurations, the function circuit modules with different operating voltage ranges are very distinguished. Since the current method of integrating these function circuit modules are difficult and complicated, the fabricating cost is increased and the production yield is unsatisfied. Therefore, there is a need of providing an improved transistor to obviate the above drawbacks.